How to implement AVR in generators

[baileychic]

How to implement AVR in AC generators ?

AVR = Automatic Voltage Regulation.

I am planning to use PIC microcontroller but it is not yet decided. I need full details about how to implement AVR. Later in this same thread I will discuss issues related to its code.

 

[KlausST]

Hi,

You need an generator with excitation coil. This generates the rotating magnetic field.
With the current of the excitation coil you influence the magnitude of the magnetic field and thus you influence the magnitude of the output voltage.

In opposite to an asynchronous generator this is a "synchronous generator" which needs a special treatment (frequency synchronisation, phase synchronisation, voltage control) before you switch it to the grid.
When connected to the grid: use the excitation current to control phase angle.

For offgrid solutions you need to continously measure the output voltage and then adjust excitation current to get constant output voltage.

Klaus

 

[baileychic]

How is magnetic field controlled ? By controlling engine speed ?

 

[KlausST]

Hi,

How is magnetic field controlled ?

As already explained:

With the current of the excitation coil you influence the magnitude of the magnetic field

Klaus

 

[FvM]

I believe you should tell more about the application so that we avoid further guessing. I guess, the application is not grid-tied, simply because controlling a grid-tied generator is surely over your head.

How is magnetic field controlled ? By controlling engine speed?

Suggests you'll read a bit about AC power and AC machines basics. Engine speed sets the AC frequency. In all applications where frequency matters (e.g. running motors), the speed must be controlled independent of the voltage.

 

[baileychic]

Client said it is grid tied. I should drop the project ?

 

[FvM]

Grid-tied is rather complicated, KlausST has listed some required functions, also you need safety features like anti-islanding control. You'll better start with studying existing industry standard generator controllers rather than designing everything from the scratch.